The present invention relates to devices for cleaning wire cables, and more particularly to a brushless cleaning device.
The conventional manner in which elevators are operated is by hoisting and lowering of the elevator car by wire cable. Wire cables are constructed of individual strands of wire that are twisted to form the cables. Typically five to six such cables are required for each elevator car installation, depending upon the load rating of the elevator and the length of the elevator's run.
FIG. 12 is a simplified illustration of a conventional signal elevator installation 10. The cables 100 extend from the elevator car 110, over the hoist machine 130 and offset wheel 120 to the counterweight 140. The offset wheel 120 is required to offset the elevator car 110 from the counterweight 140 such that each will not interfere with the travel of the other. The hoist machine 130 is typically installed on the top or intermediate floor 150 of the building and is supported by legs 135.
As seen FIG. 12, at least one side of the cables separate from the hoist machine 130 substantially perpendicular to the floor 150, while the other side of the cables separate from the machine 130 at an oblique angle. This angle is caused by the above described offset required between the counterweight 140 and the car 110. From the machine 130, the cables 100 pass through two holes 160, 170 in the floor 150 to reach the car 110 and the weight 140 respectively.
The cables 100 require lubrication in order to operate properly. In the course of operation, the cables 100 become caked with contaminants that adhere to the lubricant and to the cables 100 themselves. The contaminants consist essentially of dirt and dust. For safety reasons, the cables 100 must be periodically cleaned to remove the contaminants. Cables have usually been cleaned by hand using rags, lubricant and a wire brush. Often, cleaning was performed while the cables were in operation since halting use of the elevator for manual cleaning of cables could take the elevator out of service for several hours. As the cables typically travel at 1,400 feet/minute, manual cleaning is an inherently dangerous operation.
Various types of cleaning devices are known in the art. For example, U.S. Pat. No. 5,386,882 (the '882 patent) discloses an apparatus for mechanical holding a pair of brushes on either side of the cables. The apparatus of the '882 patent includes a U-shaped holder that is bolted directly to the floor in the area of the holes through which the elevator cables pass.
Another brush-type cleaning apparatus is disclosed in my prior U.S. Pat. No. 6,470,528.
A brushless cleaning device is disclosed in U.S. Pat. No. 5,791,011. In this device, a length of carpet is draped over the cables as they pass over the cable sheave. The carpet services to wipe the cables as they move around the sheave.
The problems associated with brush-type cleaning devices include the potential for damaging the cable surfaces over time, as well as the problem of metal filings collecting on the motor armature and field pieces The main problem with carpet type cleaners is that a relatively long length of carpet is required which once it is contaminated with sludge must be replaced. Due to its length and weight it is cumbersome and difficult to replace the carpet.